The present invention relates to carbon nitride (C1-xNx) nanotubes with nano-sized pores on their stems, their preparation method and control method of the size and the quantity of pore thereof.
A nanotube means the material of a tube or a cylindrical form with its diameter of several to several tens of nanometers.
The carbon nanotube is well known as an example of the nanotube described above.
The carbon nanotube was discovered when a carbon deposit formed at negative electrode of graphite by arc-discharge was analyzed by Dr. Iijima Sumio, Research Institute of NEC, 1991.
Such a carbon nanotube is in the tubular form in which six (6) carbon atoms form a hexagonal molecule and a plurality of these hexagonal molecules are bonded together to complete the tubular form. This tubular material was called as a ‘carbon nanotube’ because its diameter is only in the range of several to several tens of nanometers.
Various physical and chemical properties of this material, that is, the carbon nanotube have been demonstrated ever since the carbon nanotube was ascertained.
As representative properties of the carbon nanotube, electrical conductivity of the carbon nanotube is similar to that of Cu metal, its thermal conductivity is substantially equal to that of diamond and its strength is much superior, at least 100 times, to that of iron steel. The carbon nanotube can bear at best 15% of deformation thereof, whereas general carbon fibers are broken off even if only 1% of deformation is applied thereto.
Scientists have performed extensive research and investigation for synthesis and applications of the carbon nanotube after this material was disclosed. For example, it continues at present to develop many apparatuses using the carbon nanotubes such as, for example, semiconductors and flat display panels, batteries, super-intensity fibers, biometrical sensors, TV cathode ray tubes and so on. In addition, the nanotube is also used in fabrication of nano-sized tongs to pick up and move nano-sized materials.
The present invention provides the C1-xNx nanotube with nano-sized pores, which comprises carbon and nitrogen ingredients as major ingredients, and production method thereof.
Especially, the present invention can provide the C1-xNx nanotube with the controlled size and quantity of nano-sized pores by adding impurities during preparation thereof.
The C1-xNx nanotube with desirable nano-sized pores over structure of the nanotube according to the present invention exhibited a more uniform and finer dispersion of metal ingredients than that of general carbon nanotubes in the same condition for the dispersion. Since the nano-sized pores over the structure of the nanotube induce the gas adsorption energy to be increased, the nanotube is also preferably used as a gas detection sensor material. Refer for example to Han et al., Appl. Phys. Lett. 87 (2005) 213113.
Conventional technologies in relation to the present invention have proposed the C1-xNx nanotube with structure similar to that of the present invention. Refer for example to X. Ma, Appl. Phys. Lett 75(20), (1999), 3105 and G. Y. Zhang, Journal of Applied Physics, 91(11), (2002), 9324.
However, it is not certain in the art whether the nanotube proposed by X. Ma or G. Y. Zhang has nano-sized pores like as the C1-xNx nanotube of the present invention. Also, the control method of the size and quantity of nano-sized pores as described in present invention is still unknown.